FILM festival organisers want to trace the “stars” of an historic wartime documentary shot in North Wales.

Western Approaches was the first documentary to be shot in colour.

It was made by the Crown Film Unit as a tribute to the Merchant Navy, with real seamen recreating the horror of being torpedoed and sunk at sea.

During World War II the Merchant Navy kept the lifeline to America and the Commonwealth open so Britain could fight on.

Even as late as 1944, when the film was released, the convoys were still providing vital supplies.

Special colour cameras were brought from America and the cinematographer on Western Approaches was the legendary Oscar-winner Jack Cardiff.

The film crew spent six months in Holyhead and several of them courted local girls.

The North Wales Film and Television Trail is honouring the documentary with a commemorative plaque, to be unveiled on Friday.

The organisers are desperate to find anyone who may have been involved so they can attend the ceremony at the town’s Maritime Museum.

It will be a double celebration because a new war-time exhibition next to the museum is being launched on the same day.

Among the guests will be retired shipwright John Parry, now 82, who has vivid memories of the filming.

A 15-year-old apprentice at the time, he recalls being totally baffled when a lifeboat was delivered to the dockside and promptly cut in half.

The stern section remained on dry land and was used to film the close-up shots of the torpedoed merchant seamen.

Mr Parry said: “They used to walk to the dock every morning from town. These men were genuine Merchant Navy seafarers who had lost their ship during the war.

“The cameraman filmed 10 or 11 people in the half boat. They were obviously meant to be at sea and they were throwing water over these fellows.

“They had another lifeboat in the water and a motor fishing vessel which towed them out behind the breakwater where they did a lot of the filming.

“They had a 20ft long pole with a weight on the bottom, with just two feet sticking out of the water – this was a submarine periscope which was actually being towed by the MFV.

“It was very clever because you’d swear it was the real thing, you can see it in the film.

“They had to wear the same clothes for six months. There was one particular guy who was wearing a bandage, they’d put on some red paint for blood.

“That bandage became dirtier and dirtier and you can see it in the film – it became filthy by the end.

“It was very exciting for a 15-year-old boy. There was a lovely young girl, a little bit older than me, who was doing the continuity. I would have given anything to go on a date with her.”

Richard Burnell, vice chairman of the Maritime Museum said: “It was cutting edge stuff. It’s quite a film when you look it, a classic of its type. “It would be brilliant it there was anybody out there who was involved with the film in some way and they were able to come along to the ceremony on Friday.”